Electric power consumption is being rapidly increased due to global warming and industrial development, and thus an energy storage apparatus (energy storage system; ESS) has been utilized as an efficient alternative in order to satisfy demands for electric power which are increased.
The energy storage apparatus serves to store excessively produced electric power, and transmit the electric power when electric power is insufficient, and the energy storage apparatus may be installed and managed in power generation systems and power transmission and distribution systems of electric power system, and consumer houses, and utilized for various functions such as new regenerative energy output stabilization and an emergency power source.
In this case, the energy storage apparatus stores several to several hundreds of battery modules in order to stably store high capacity energy, and the battery modules are stacked on a battery rack in order to minimize a spatial requirement.
In general, because there is a limitation to a size of a container that stores the energy storage apparatus, it is necessary to increase spatial utilization of the battery rack for an efficient spatial use.
In the case of a container for an energy storage apparatus in the related art, support frames are made in the container, and the battery rack in the form of a finished product is coupled to the container, and as a result, a lower end of the battery rack and a side frame are overlapped during this process, so that a space is unnecessarily wasted.